Operating mechanism for ejector gate and apron of self-loading scrapers



Sept. 5, 1961 v. E. REZABEK 2,998,662

OPERATING MECHANISM FOR EJEcToR GATE AND APRoN oF SELF-LOADING scRAPERs QTOEN Eg/ Sept. 5, 1961 v. E. REZABEK 2,998,662

OPERATING MECHANISM FOR EJEcToR GATE AND APRoN oF SELF-LOADING scRAPERs 4 Sheets-Sheet 2 Filed Feb. 4, 1960 VE/QNON Sept. 5, 1961 v. E. REzABl-:K 2,998,662

OPERATING MECHANIsA/f` FOR EJECTOR GATE AND APRoN oF SELF-LOADING scRAPERs Filed Feb. 4, 1960 4 sheets-sheet s HA f n ll .JI-:

ZNVENTOE V NOA/ EZQEK @J7-@EN Eg/ Sept. 5, 1961 v. E. REZABEK 2,998,662

OPERATING MECHANISM FOR EJECTOR GATE AND APRON OF SELF-LOADING SCRAPERS Filed Feb. 4, 1960 4 Sheets-Sheet 4 V NON 5529.695

Q17 O EN Ec/ United States Patent OPERATING MECHAISI FOR EJ-EC'IGR GATE AND APRON F SELF-LOADING SCRAPERS Vernon E. Rezabek, Palatine, Ill., assignor tot International Harvester Company, Chicago, Ill., a corporation of New Jersey Filed Feb. 4, 1960, Ser. No. 6,657 4 Claims. (Cl. 37h-1126) This invention relates to self-loading Scrapers particularl'y adapted for earth moving operations. More particularly the invention relates to a scraper of a type having a load-carrying bowl including a load-retaining apron, and having an ejector gate movable longitudinally within the bowl for ejecting earth or other material therefrom.

In the pending patent application of Robert C. Storck, Serial No. 774,246, tiled November 17, 1958, an improved self-loading scraper is described. This scraper includes an improved apron and ejector gate actuating device with the ejector gate returned by means of a tension spring which is subject to changes in tension during the raising and lowering of the apron.

The type of self-loading scraper to which the present invention refers comprises a cutting blade which extends transversely across the bottom of the load-carrying bowl at its forward portion thereof. At this lforward portion the bowl is also provided with a gate commonly referred to as an apron, the apron including a lower rear edge portion which is moved forwardly and upwardly with respect to the cutting edge of the bowl thereby either opening the bowl for the entrance or discharge of earth and for closing the same during transit. The earth which enters into the bowl is also partly carried by the apron, the apron providing an ample space which with the main body of the bowl carries the material received. When it is desired to unload the scraper bowl, the apron is swung forwardly and upwardly to allow the portion of the load carried thereby to pour downwardly from the apron to the spot which may be desired. In addition, the ejector gate is movable forwardly to advance the dirt and -to discharge the same from the forward portion of the bowl. The forward movement of the ejector gate is of course resisted by the load resting upon the bottom of the scraper.

In the aforementioned application, however, movement of the `gate is also resisted by the force of an ejector gate return spring, which upon such forward movement increases in tension and helps to return the ejector gate after the load has been discharged. In the aforementioned improvement, the return spring is provided with a control arrangement which makes it possible to diminish the size and weight of the spring, the said spring elongation or tension being diminished by virtue of this `control and yet being effective for adequate and positive retraction of the ejector gate. The control arrangement is actuated by means of a cable which is placed in a takeup or tensioned position causing the apron to initially raise prior to the forward movement of the ejector gate. This, of course, is necessary to permit discharging of the forward portion of the load prior to the movement of the ejector so that the movement of the load is not unnecessarily impeded. To effectuate such a preliminary opening and sequential operation of the apron and ejector, the aforementioned application discloses a certain cable reeving arrangement. It is a prime object of this invention to provide an improved cable reeving arrangement and mechanism which will more positively result in the initial opening of the apron prior to movement of the ejector gate upon take-up of the cable lby suitable operator actuated means.

Another object of this invention is to provide an im- Patented Sept. 5, 1961 proved cable reeving arrangement assuring sequential operation of a bowl apron and ejector gate.

A still further object is the provision of an improved apron and ejector gate control arrangement having an improved spring tensioning system, the said system including a novel and improved cable reeving arrangement whereby sequential operation of the apron and ejector gate is assured.

A more specific object is the provision of an improved control arrangement, including a spring tensioning means, the said control arrangement having associated therewith a cable reeving system consisting of a plurality of sheave units and sheaves around which flights of cables are trained, the said sheaves being located and arranged to provide a greater force differential, upon take-up of the cable, between the apron and the ejector gate so that the apron is initially moved to an open position prior to movement of the ejector gate advancively toward the forward portion of the bowl.

Still another object is the provision of an improved cable reeving arrangement designed to provide a single cable for opening the apron of the scraper prior to the movement of the ejector gate7 the said arrangement also preventing forward creep of the ejector gate when the bowl is empty and the apron is raised.

These and other objects will become more readily apparent `from a reading of the specification vwhen examined in connection with the accompanying sheets of drawings.

In the drawings:

FIG. 1 is a fragmentary side elevational view of a self-loading scraper, with portions broken away and other portions shown in section to illustrate components of a preferred embodiment of the present invention incorporated in the scraper;

FIG. 2 is an enlarged diagrammatic side elevational view of the rear portion of the scraper shown in FIG. l;

FIG. 3 is a side elevational view of a portion of a scraper, in diagrammatic form, showing an operating position of the gate ejection mechanism;

FIG. 4 is a diagrammatic view of an apron and gate actuating mechanism showing the cable reeving therefor;

FIG. 5 is an enlarged side elevational view of a spring anchorage member and apron opening unit; and

FIG. 6 is a rear elevational view of a portion of the unit shown in FIG. 5.

Referring now particularly to FIGS. l, 2 and 3, a scraper is generally designated by the reference character 10. The scraper 10 comprises a draft frame 11 consisting of a pair of arms 12 which are pivoted as indicated at 13 to the sides of a scraper bowl 14. The arms 12 are suitably supported by means of a gooseneck V15, which in turn is pivotally mounted on a wheeled truck or tractor 16 suitably supported by ground wheels 17.

The sides of the scraper bowl are indicated at 18 and the bowl includes a front end portion 19 and Ia materialcarrying bottom 20. The bowl is provided with a discharge opening 21 which is closed by means of an apron 22 suitably pivoted as indicated at 23. The apron 22 is also provided with an arm 24.

The bowl is supported on a rear frame 25 comprising upper and lower laterally spaced frame members 26. The frame 25 further includes upper and lower transverse frame members 27 suitably connected to the f-ramemembers 26. Vertical side plates 29 are transversely spaced and connected to the upper and lower frame members 26. The plates 29 -also suitably secure a horizontal support 30. The frame members 26 are connectedat their rear by a pusher structure 31 including a pair of laterally spaced Vertical plates 32. Upper support brackets 33 are also suitably supported on the frame structure 25. A transversely extending shaft 34 is suitably journalled on the brackets 33, the said shaft 34 also having connected thereto for rotation therewith an arm 35. A tension link 36 is pivotally connected to the -arm 35 as indicated at 37. The link 36 is connected at another end to the arm 24 as indicated at 38.

A spring anchorage member is generally designated at 39. The spring anchorage member 39 comprises a pair of laterally spaced plates 40 which are suitably keyed to the shaft 34. As shown in FIG. 5, the plates 40 support a sheave unit 42 comprising a housing 43 having side plates 44 suitably connected to the plates 40. The housing 43 has supported thereon a pair of anchorage ears 45. A stop 46 is provided on one of the plates 29, the said stop, as shown in FIG. 3, being engaged by forward faces 47 of the plates. As best shown in FIGS. 3 and 4, a pair of sheaves 48 and 49 are journalled on a shaft 50 which in turn is supported on one of the vertical plate members 29, the said shaft 50 extending through an opening 51. A sheave 52 rotatable on a shaft 53 is supported on the other plate member 29 by being supported within an opening 51 thereof.

An ejector gate as shown in FIG. l is designated at 54. The ejector gate 54 includes a stern 55 which is rigidly connected there and which is supported on the horizontal support 30. A bracket 56 is supported on the rear of the stem 55, the said bracket having mounted thereon a shaft 57 upon which a sheave unit 58 is journalled.

A spring structure is designated at 59, the spring structure comprising an adjustment rod 60 which is suitably connected to the ejector gate 54 by means of nuts 61. The rod 60 has connected thereto a bracket 62 to which springs 63 are secured. The `springs 63 are also secured at their rearmost ends to a bracket 64. A sheave 65 is suitably journalled on one of the plates 32 by means of a shaft 66, the shaft being supported in an opening 67, as indicated in FIG. 4. As best shown in FIGS. 2 and 3, a cable 68 has one end firmly connected to the anchorage ears 45, is trained about the sheave 65 and is suitably connected to the brackets 64 as indicated at 69.

Referring now to FIG. 4, the sheave unit 42 comprises a plurality of sheaves A, B, C, D, E, F and G, and the sheave unit 58 comprises sheaves H, I, I and K. A cable 70 has its end suitably connected to a winch mechanism (not shown), the said winch mechanism being adapted to reel in and tension the cable 70 or to let out the cable 70. The cable 70 is suitably wound about guide sheaves 71, 72 and 73 which may be suitably supported on p0rtions of the scraper. The winch unit is usually carried on the truck or tractor to which the scraper is attached. The cable 70 is wound about the sheave 48 and extends to the sheave A, whereupon it extends over the sheave 49 to the sheave B and from the sheave B to the sheave H. It ex tends around the sheave H to the sheave C, around the sheave C to the sheave I, and around the sheave I to the sheave D. It extends around the sheave D to the sheave I, around the sheave I to the sheave E, around the sheave E to the sheave K, and around the sheave K to the sheave F. IIt extends around the sheave F to and around the sheave 52, around and over the sheave G to the cable wedge lock 74, the said cable wedge lock being suitably connected to a portion of the frame 25 in a conventional manner.

Operation The apron 22 is normally in the position shown in FIG. l. When it is desired to load the bowl with earth a cable 75, -as shown in FIG. l, is permitted to wind out from the cable control unit and the bowl is lowered. The cable 75 is wound around a sheave 76 which in turn is carried on a bracket 77 on the front portion 19 of the bowl, the said cable being locked to one of the dra-ft arms 12 as indicated at 78. The bowl thus is lowered and simultaneously the cable control unit takes up the cable 70. As the cable 70 is tensio'ned to spring anchorage member 39 is moved rearwardly causing the link 36 to pivot the arm 24 whereupon the apron 22 is raised. As the spring anchorage means 39 is moved rearwardly the 4 portions 47 engage the stop 46 and the scraper now can be loaded.

After the scraper is loaded the apron is returned to its original position and the load may be transported to its destination. When the scraper reaches its destination the same operation is repeated. However, at this point it is desired to discharge the load and the ejector gate 54 must be advanced Atoward the opening 21. Therefore continued take-up of the cable 70 occurs and since the anchorage means 39 is in engagement with the stop 46, this continued take-up of the cable causes the distance between the sheave units 42 and 58 to decrease. Since the sheave unit 58 is connected to the stem 55, the stem is moved forwardly or advanced in the direction of the opening 21, thereupon discharging the load on the bottom 20. As the gate 54 moves forwardly the spring unit 59 is placed in tension. After the load has been discharged the cable control unit lets out the cable 70 and the spring anchorage means 39 is pivoted forwardly by the apron dropping due to normal gravity. Simultaneously with the lowering of the apron the spring 63 serves to exert a pull on the gate 54 to retract the same to its original position. The cooperation and action of the spring anchorage means 39 and the spring mechanism 59 can be further described as follows:

As the cable 70 is wound up on a tractor mounted winch the distance between the sheave units 42 and 58 diminishes. The load within the scraper exerts a force maintaining the ejector gate 54 in position. Thus upon continued take-up of the cable, the spring anchorage member 39 initially will pivot to raise the apron. When the apron is fully raised, the `arm 39 has moved to its stop position at 46, and continued shortening of the distance between the sheave units will effect the discharge of the load since the gate 54 is advanced forwardly. It is of course desirable to assure the positive opening of the apron prior to the discharge of the load and this is assured by the reeving arrangement and the sheave units as shown in FIG. 4. The flights of cable between the sheave units 42 and 58 are eight flights, considering a flight to be an upper or lower running of the cable 70. On the other hand, by virtue of the arrangement of the sheaves 48, 49 and 52, in cooperation with the sheave unit 42 six additional flights are apparent. This results in a fourteen to eight force differential whereby a tension upon the cable 70 will place a greater force effort on the Aarm 39 to cause the same to pivot. Therefore the initial tension serves to positively force the apron to its open position prior to the movement of the stem causing movement of the ejector gate.

The operation of the spring mechanism and the spring anchorage means has been fully described and further is supplemented in the above mentioned application. In the present invention the sheave unit and arrangement including the sheaves 48, 49 and 52 assure the initial operation of the apron by the force differential resulting from the arrangement. It is obvious that while the bowl is empty the ejector gate 54 will not creep during the opening of the apron for initial loading since the force differential positively assures raising of the apron and immediate pivotal action of the anchorage member 39.

Thus it is believed that the objects of the invention have been fully achieved and that an improved apronopening and load-ejecting mechanism has been shown and described. It must be understood that changes and modifications may be made without departing from the spirit of the invention as disclosed or from the scope thereof as defined in the appended claims.

What is claimed is:

l. In a self-loading scraper, a scraper frame, a loadcarrying bowl on said frame, said bowl including a loadretaining apron forming a forward portion thereof and liftable from a lowered load-retaining position to a loaddumping position, an ejector gate retractable into a rearward portion of the bowl and being advanceable forwardly from such rearward portion to discharge a load from the bowl when the apron is raised, a spring anchorage means movable forwardly and rearwardly with respect to said ejector gate, connecting means connecting said spring anchorage means to said apron to raise Ithe same during rearward movement of said anchorage means and said spring anchorage means being movable forwardly during lowering rof said apron by gravity, an ejector gate return spring connected between such gate and said spring anchorage means, said spring being stressed attendant to advancement of the gate relative to the anchorage to in crease the force with which the spring retractively urges said gate, said stress in said spring being decreased during rearward movement of said spring anchorage means, means for moving said spring anchorage means rearwardly comprising a first sheave unit connected to said gate, said first sheave unit including a plurality of first sheaves, -a second sheave unit positioned on said spring anchorage means, said second unit including a plurality of second sheaves, a pair of third sheaves secured to said frame adjacent one side of said second sheave unit, a fourth sheave secured to said frame adjacent an opposite side of said second unit, a line reeved between certain of said first and second sheaves to provide a plurality of irst flights, and reeved between said third and fourth sheaves and certain other of said second sheaves to provide second flights, whereby during take-up of said line said flights provide a force differential with respect to said spring anchorage means and said gate whereupon said spring anchorage means is moved initially and the distance between said iirst and second units is decreased and whereupon continued take-up of said line said ejector gate is then moved forwardly.

2. In a self-loading scraper, a scraper frame, a loadcarrying bowl on said frame, said bowl including a loadretaining apron forming a forward portion thereof and liftable from a lowered load-retaining position to a loaddumping position, an ejector gate retractable into a rearward portion of the bowl and being advanceable forwardly from such rearward portion to discharge a load from the bowl when the apron is raised, a spring anchorage means movable forwardly and rearwardly with respect to said ejector gate, connecting means connecting said spring anchorage means to said apron to raise the same during rearward movement of said anchorage means `and said spring anchorage means being movable forwardly during lowering of said apron by gravity, an ejector gate return spring connected between such gate and said spring anchorage means, said spring being stressed attendant to advancement of the gate relative to the anchorage to increase the force with which the spring retractively urges said gate, said stress in said spring being decreased during rearward movement of said spring anchorage means, means for moving said spring anchorage rearwardly comprising a rst sheave unit connected to said gate, said irst sheave unit including a plurality of first sheaves, la second sheave unit positioned on said spring yanchorage means, said second unit including a plurality of second sheaves of greater number than the sheaves of said first unit, third sheaves stationarily secured to said frame, a line reeved between certain of said irst and second sheaves to provide a plurality of first flights, and reeved between said third sheaves and certain other of said second sheaves to provide second flights, whereby during take-up of said line said flights provide a force differential with respect to said spring lanchorage means and said gate whereupon said spring anchorage means is moved initially and the distance between said irst and second units is decreased and whereupon continued talte-up of said line said ejector gate is then moved forwardly.

3. In a self-loading scraper, a scraper frame, a loadcarryirrg bowl on said frame, said bowl including a load-retaining apron forming a forward portion thereof and liftable from a lowered load-retaining position to a load-dumping position an ejector gate retractable into a rearward portion of the bowl and being advanceable forwardly from such rearward portion to discharge a load from the bowl when the apron is raised, a spring anchorage means movable forwardly and rearwardly with respect to said ejector gate, connecting means connecting said spring anchorage means to said apron to raise the same during rearward movement of said anchorage means and said spring anchorage means being movable forwardly during lowering of said apron by gravity, an ejector gate return spring 'connected between such gate and said spring anchorage means, said spring being stressed attendant to advancement of the gate relative to the anchorage to increase the force with which the spring retractively urges said gate, said stress in said spring being decreased during rearward movement of said spring anchorage means, means for moving said spring anchorage means rearwardly comprising a first sheave unit connected to said gate, said first sheave unit including a plurality of first sheaves, a second sheave unit associated with said spring anchorage means, said second unit including a plurality of second sheaves of greater number than the sheaves of said first unit, a set of third sheaves associated with said second unit, a line reeved between certain of said irst and second sheaves, and reeved between said third and certain other of said second sheaves, whereby during take-up of said line said reeving and said sheaves provide a force diiferential with respect to said spring anchorage means and said gate whereupon said spring anchorage means is moved initially and the distance between said first and second units is decreased and whereupon continued take-up of said line said ejector gate is then moved forwardly.

4. In a self-loading scraper, a scraper frame, a loadcarrying bowl on said frame, said bowl including a load-retaining apron forming a forward portion thereof and liftable from a lowered load-retaining position to a load-dumping position, an ejector gate retractable into a rearward portion of the bowl and being advanceable forwardly from such rearward portion to discharge a load from the bowl when the apron is raised, a spring anchorage means movable forwardly and rearwardly with respect to said ejector gate, connecting means connecting said spring anchorage means to said apron to raise the same dining rearward movement of said anchorage means and said spring anchorage means being movable forwardly during lowering of said apron by gravity, an ejector gate return spring connected between such gate and said spring anchorage means, said spring being stressed attendant to advancement of the gate relative to the anchorage to increase the force with which the spring retractively urges said gate, said stress in said spring being decreased during rearward movement of said spring anchorage means, means for moving said spring anchorage means rearwardly comprising a iirst sheave unit connected to said gate, said first sheave unit including a plurality of iirst sheaves, a second sheave unit positioned on said spring anchorage means, said second unit including a plurality of second sheaves having a greater number of sheaves than the sheaves of said unit, a line reeved between certain of said second sheaves and said first sheave unit to provide a plurality of ights, a third sheave means disposed between said first and second sheave units, and reeved around said third sheave means and certain of said second sheaves whereby during take-up of said line said reeving and said sheaves and sheave means provide a force differential with respect to said spring anchorage means and said gate whereupon said spring anchorage means is moved initially and the distance between said first and second units is decreased and whereupon continued take-up of said line said ejector gate is then moved forwardly.

References Cited in the le of this patent UNITED STATES PATENTS 2,447,455 Anm Aug. 11. 194g 

